Differentiation of human embryonic stem cells

1. An in vitro cell culture comprising an isolated population of cells and a culture medium suitable for differentiating pluripotent stem cells,

wherein greater than 85% of the cells are definitive endoderm cells,

wherein said population of cells is obtained by differentiating in vitro pluripotent stem cells,

wherein the culture medium lacks serum and is supplemented with BSA, GDF-8, 14-Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and a factor selected from the group consisting of insulin and from about 1 ng/ml to about 50 ng/ml of IGF-1, and

wherein said definitive endoderm cells express CXCR4 and do not express CD9.

2. The in vitro culture of claim 1 , wherein the isolated population of cells is obtained without further purifying the cells after differentiation.

3. The in vitro culture of claim 1 , wherein the medium is further supplemented with activin A and Wnt-3.

4. The in vitro culture of claim 1 , wherein the medium is chemically-defined.

5. A method for generating a population of cells wherein greater than 85% of the cells in the population are definitive endoderm cells, comprising the steps of:

a. culturing a population of pluripotent stem cells; and

b. differentiating the population of pluripotent stem cells to a population of cells wherein greater than 85% of the cells in the population are definitive endoderm cells in medium lacking serum and supplemented with BSA, GDF-8, 14-Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and a factor selected from the group consisting of insulin and from about 1 ng/ml to about 50 ng/ml of IGF-1.

6. The method of claim 5 , wherein the population of pluripotent stem cells is differentiated in the medium lacking serum and supplemented with BSA and a factor selected from the group consisting of insulin and from about 1 ng/ml to about 50 ng/ml of IGF-1 for a period of at least 6 days.

7. The method of claim 5 , wherein the population of pluripotent stem cells is differentiated in the medium lacking serum and supplemented with BSA and a factor selected from the group consisting of insulin and from about 1 ng/ml to about 50 ng/ml of IGF-1 for a period of at least 7 days.

8. The method of claim 5 , wherein the step of differentiating comprises treating the pluripotent stem cells with a medium lacking serum and supplemented with BSA, GDF-8, 14-Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and from about 1 ng/ml to about 50 ng/ml of IGF-1.

9. The method claim 5 , wherein the population of cells is obtained without further purifying the cells after differentiation.

10. The method of claim 5 , wherein the step of differentiating comprises treating the pluripotent stem cells with a medium lacking serum and supplemented with BSA, GDF-8, 14-Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and insulin.

11. The method of claim 5 , wherein the step of differentiating comprises treating the pluripotent stem cells with a medium lacking serum and supplemented with BSA, from about 5 ng/ml to about 500 ng/ml of GDF-8, 14-Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and a factor selected from the group consisting of insulin and from about 1 ng/ml to about 50 ng/ml of IGF-1.

12. The method of claim 5 , wherein the step of differentiating comprises treating the pluripotent stem cells with a medium lacking serum and supplemented with from about 0.5 to about 2% BSA, GDF-8, 14-Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and a factor selected from the group consisting of insulin and from about 1 ng/ml to about 50 ng/ml of IGF-1.

13. The method of claim 5 , wherein the step of differentiating comprises treating the pluripotent stem cells with a medium lacking serum and supplemented with BSA, GDF-8, 14-Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and from about 1 ng/ml to about 100 ng/ml of insulin.

14. The method of claim 5 , wherein the step of differentiating comprises treating the pluripotent stem cells with a medium lacking serum and supplemented with about 2% BSA, GDF-8, 14-Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and from about 1 ng/ml to about 50 ng/ml of IGF-1.

15. The method of claim 5 , wherein the medium is chemically-defined.

16. An in vitro culture comprising an isolated population of cells in which greater than 85% of the cells are definitive endoderm cells and a cell culture medium,

wherein said population of cells is obtained by differentiating pluripotent stem cells into definitive endoderm cells, and

wherein the cell culture medium lacks serum and is supplemented with BSA, GDF-8, 14- and Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1-8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and either insulin or from about 1 ng/ml to about 50 ng/ml of IGF-1.

17. The in vitro culture of claim 16 , wherein the population is obtained by differentiating pluripotent stem cells into definitive endoderm cells by treating the pluripotent stem cells with the medium lacking serum and supplemented with BSA, GDF-8, 14- and Prop-2-en-1-yl-3,5,7,14,17,23,27-heptaazatetracyclo[19.3.1.1˜2,6˜0.1˜8,12˜]heptacosa-1(25),2(27),3,5,8(26),9,11,21,23-nonaen-16-one and either insulin or from about 1 ng/ml to about 50 ng/ml of IGF-1.